﻿using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Drawing.Design;
using System.Text;
using System.Windows.Forms;
using System.Collections;
using System.Reflection;
using System.Runtime.InteropServices;

/// <summary>
/// DataGridView行合并.请对属性MergeColumnNames 赋值既可
/// </summary>
public partial class RowMergeView : DataGridView
{
  #region 构造函数
  public RowMergeView()
  {
    InitializeComponent();
  }
  #endregion
  #region 重写的事件
  protected override void OnPaint(PaintEventArgs pe)
  {
    // TODO: 在此处添加自定义绘制代码

    // 调用基类 OnPaint
    base.OnPaint(pe);
  }
  protected override void OnCellPainting(DataGridViewCellPaintingEventArgs e)
  {
    try
    {
      if (e.RowIndex > -1 && e.ColumnIndex > -1)
      {
        //DrawCell(e);
      }
      else
      {
        //二维表头
        if (e.RowIndex == -1)
        {
          if (SpanRows.ContainsKey(e.ColumnIndex)) //被合并的列
          {
            //画边框
            Graphics g = e.Graphics;
            e.Paint(e.CellBounds, DataGridViewPaintParts.Background | DataGridViewPaintParts.Border);

            int left = e.CellBounds.Left, top = e.CellBounds.Top + 2,
            right = e.CellBounds.Right, bottom = e.CellBounds.Bottom;

            switch (SpanRows[e.ColumnIndex].Position)
            {
              case 1:
                left += 2;
                break;
              case 2:
                break;
              case 3:
                right -= 2;
                break;
            }

            //画上半部分底色
            g.FillRectangle(new SolidBrush(this._mergecolumnheaderbackcolor), left, top,
            right - left, (bottom - top) / 2);

            //画中线
            g.DrawLine(new Pen(this.GridColor), left, (top + bottom) / 2,
            right, (top + bottom) / 2);

            //写小标题
            StringFormat sf = new StringFormat();
            sf.Alignment = StringAlignment.Center;
            sf.LineAlignment = StringAlignment.Center;

            g.DrawString(e.Value + "", e.CellStyle.Font, Brushes.Black,
            new Rectangle(left, (top + bottom) / 2, right - left, (bottom - top) / 2), sf);
            left = this.GetColumnDisplayRectangle(SpanRows[e.ColumnIndex].Left, true).Left - 2;

            if (left < 0) left = this.GetCellDisplayRectangle(-1, -1, true).Width;
            right = this.GetColumnDisplayRectangle(SpanRows[e.ColumnIndex].Right, true).Right - 2;
            if (right < 0) right = this.Width;

            g.DrawString(SpanRows[e.ColumnIndex].Text, e.CellStyle.Font, Brushes.Black,
            new Rectangle(left, top, right - left, (bottom - top) / 2), sf);
            e.Handled = true;
          }
        }
      }
      base.OnCellPainting(e);
    }
    catch
    { }
  }
  protected override void OnCellClick(DataGridViewCellEventArgs e)
  {
    base.OnCellClick(e);
  }
  #endregion
  #region 自定义方法
  /// <summary>
  /// 画单元格
  /// </summary>
  /// <param name="e"></param>
  private void DrawCell(DataGridViewCellPaintingEventArgs e)
  {
    if (e.CellStyle.Alignment == DataGridViewContentAlignment.NotSet)
    {
      e.CellStyle.Alignment = DataGridViewContentAlignment.MiddleCenter;
    }
    Brush gridBrush = new SolidBrush(this.GridColor);
    SolidBrush backBrush = new SolidBrush(e.CellStyle.BackColor);
    SolidBrush fontBrush = new SolidBrush(e.CellStyle.ForeColor);
    int cellwidth;
    //上面相同的行数
    int UpRows = 0;
    //下面相同的行数
    int DownRows = 0;
    //总行数
    int count = 0;
    if (this.MergeColumnNames.Contains(this.Columns[e.ColumnIndex].Name) && e.RowIndex != -1)
    {
      cellwidth = e.CellBounds.Width;
      Pen gridLinePen = new Pen(gridBrush);
      string curValue = e.Value == null ? "" : e.Value.ToString().Trim();
      string curSelected = this.CurrentRow.Cells[e.ColumnIndex].Value == null ? "" : this.CurrentRow.Cells[e.ColumnIndex].Value.ToString().Trim();
      if (!string.IsNullOrEmpty(curValue))
      {
        #region 获取下面的行数
        for (int i = e.RowIndex; i < this.Rows.Count; i++)
        {
          if (this.Rows[i].Cells[e.ColumnIndex].Value.ToString().Equals(curValue))
          {
            //this.Rows[i].Cells[e.ColumnIndex].Selected = this.Rows[e.RowIndex].Cells[e.ColumnIndex].Selected;

            DownRows++;
            if (e.RowIndex != i)
            {
              cellwidth = cellwidth < this.Rows[i].Cells[e.ColumnIndex].Size.Width ? cellwidth : this.Rows[i].Cells[e.ColumnIndex].Size.Width;
            }
          }
          else
          {
            break;
          }
        }
        #endregion
        #region 获取上面的行数
        for (int i = e.RowIndex; i >= 0; i--)
        {
          if (this.Rows[i].Cells[e.ColumnIndex].Value.ToString().Equals(curValue))
          {
            //this.Rows[i].Cells[e.ColumnIndex].Selected = this.Rows[e.RowIndex].Cells[e.ColumnIndex].Selected;
            UpRows++;
            if (e.RowIndex != i)
            {
              cellwidth = cellwidth < this.Rows[i].Cells[e.ColumnIndex].Size.Width ? cellwidth : this.Rows[i].Cells[e.ColumnIndex].Size.Width;
            }
          }
          else
          {
            break;
          }
        }
        #endregion
        count = DownRows + UpRows - 1;
        if (count < 2)
        {
          return;
        }
      }
      if (this.Rows[e.RowIndex].Selected)
      {
        backBrush.Color = e.CellStyle.SelectionBackColor;
        fontBrush.Color = e.CellStyle.SelectionForeColor;
      }
      //以背景色填充
      e.Graphics.FillRectangle(backBrush, e.CellBounds);
      //画字符串
      PaintingFont(e, cellwidth, UpRows, DownRows, count);
      if (DownRows == 1)
      {
        e.Graphics.DrawLine(gridLinePen, e.CellBounds.Left, e.CellBounds.Bottom - 1, e.CellBounds.Right - 1, e.CellBounds.Bottom - 1);
        count = 0;
      }
      // 画右边线
      e.Graphics.DrawLine(gridLinePen, e.CellBounds.Right - 1, e.CellBounds.Top, e.CellBounds.Right - 1, e.CellBounds.Bottom);

      e.Handled = true;
    }
  }
  /// <summary>
  /// 画字符串
  /// </summary>
  /// <param name="e"></param>
  /// <param name="cellwidth"></param>
  /// <param name="UpRows"></param>
  /// <param name="DownRows"></param>
  /// <param name="count"></param>
  private void PaintingFont(System.Windows.Forms.DataGridViewCellPaintingEventArgs e, int cellwidth, int UpRows, int DownRows, int count)
  {
    SolidBrush fontBrush = new SolidBrush(e.CellStyle.ForeColor);
    int fontheight = (int)e.Graphics.MeasureString(e.Value.ToString(), e.CellStyle.Font).Height;
    int fontwidth = (int)e.Graphics.MeasureString(e.Value.ToString(), e.CellStyle.Font).Width;
    int cellheight = e.CellBounds.Height;

    if (e.CellStyle.Alignment == DataGridViewContentAlignment.BottomCenter)
    {
      e.Graphics.DrawString((String)e.Value, e.CellStyle.Font, fontBrush, e.CellBounds.X + (cellwidth - fontwidth) / 2, e.CellBounds.Y + cellheight * DownRows - fontheight);
    }
    else if (e.CellStyle.Alignment == DataGridViewContentAlignment.BottomLeft)
    {
      e.Graphics.DrawString((String)e.Value, e.CellStyle.Font, fontBrush, e.CellBounds.X, e.CellBounds.Y + cellheight * DownRows - fontheight);
    }
    else if (e.CellStyle.Alignment == DataGridViewContentAlignment.BottomRight)
    {
      e.Graphics.DrawString((String)e.Value, e.CellStyle.Font, fontBrush, e.CellBounds.X + cellwidth - fontwidth, e.CellBounds.Y + cellheight * DownRows - fontheight);
    }
    else if (e.CellStyle.Alignment == DataGridViewContentAlignment.MiddleCenter)
    {
      e.Graphics.DrawString((String)e.Value, e.CellStyle.Font, fontBrush, e.CellBounds.X + (cellwidth - fontwidth) / 2, e.CellBounds.Y - cellheight * (UpRows - 1) + (cellheight * count - fontheight) / 2);
    }
    else if (e.CellStyle.Alignment == DataGridViewContentAlignment.MiddleLeft)
    {
      e.Graphics.DrawString((String)e.Value, e.CellStyle.Font, fontBrush, e.CellBounds.X, e.CellBounds.Y - cellheight * (UpRows - 1) + (cellheight * count - fontheight) / 2);
    }
    else if (e.CellStyle.Alignment == DataGridViewContentAlignment.MiddleRight)
    {
      e.Graphics.DrawString((String)e.Value, e.CellStyle.Font, fontBrush, e.CellBounds.X + cellwidth - fontwidth, e.CellBounds.Y - cellheight * (UpRows - 1) + (cellheight * count - fontheight) / 2);
    }
    else if (e.CellStyle.Alignment == DataGridViewContentAlignment.TopCenter)
    {
      e.Graphics.DrawString((String)e.Value, e.CellStyle.Font, fontBrush, e.CellBounds.X + (cellwidth - fontwidth) / 2, e.CellBounds.Y - cellheight * (UpRows - 1));
    }
    else if (e.CellStyle.Alignment == DataGridViewContentAlignment.TopLeft)
    {
      e.Graphics.DrawString((String)e.Value, e.CellStyle.Font, fontBrush, e.CellBounds.X, e.CellBounds.Y - cellheight * (UpRows - 1));
    }
    else if (e.CellStyle.Alignment == DataGridViewContentAlignment.TopRight)
    {
      e.Graphics.DrawString((String)e.Value, e.CellStyle.Font, fontBrush, e.CellBounds.X + cellwidth - fontwidth, e.CellBounds.Y - cellheight * (UpRows - 1));
    }
    else
    {
      e.Graphics.DrawString((String)e.Value, e.CellStyle.Font, fontBrush, e.CellBounds.X + (cellwidth - fontwidth) / 2, e.CellBounds.Y - cellheight * (UpRows - 1) + (cellheight * count - fontheight) / 2);
    }
  }
  #endregion
  #region 属性
  /// <summary>
  /// 设置或获取合并列的集合
  /// </summary>
  [MergableProperty(false)]
  [Editor("System.Windows.Forms.Design.ListControlStringCollectionEditor, System.Design, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a", typeof(UITypeEditor))]
  [DesignerSerializationVisibility(System.ComponentModel.DesignerSerializationVisibility.Visible)]
  [Localizable(true)]
  [Description("设置或获取合并列的集合"), Browsable(true), Category("单元格合并")]
  public List<string> MergeColumnNames
  {
    get
    {
      return _mergecolumnname;
    }
    set
    {
      _mergecolumnname = value;
    }
  }
  private List<string> _mergecolumnname = new List<string>();
  #endregion
  #region 二维表头
  private struct SpanInfo //表头信息
  {
    public SpanInfo(string Text, int Position, int Left, int Right)
    {
      this.Text = Text;
      this.Position = Position;
      this.Left = Left;
      this.Right = Right;
    }

    public string Text; //列主标题
    public int Position; //位置，1:左，2中，3右
    public int Left; //对应左行
    public int Right; //对应右行
  }
  private Dictionary<int, SpanInfo> SpanRows = new Dictionary<int, SpanInfo>();//需要2维表头的列
  /// <summary>
  /// 合并列
  /// </summary>
  /// <param name="ColIndex">列的索引</param>
  /// <param name="ColCount">需要合并的列数</param>
  /// <param name="Text">合并列后的文本</param>
  public void AddSpanHeader(int ColIndex, int ColCount, string Text)
  {
    if (ColCount < 2)
    {
      throw new Exception("行宽应大于等于2，合并1列无意义。");
    }
    //将这些列加入列表
    int Right = ColIndex + ColCount - 1; //同一大标题下的最后一列的索引
    SpanRows[ColIndex] = new SpanInfo(Text, 1, ColIndex, Right); //添加标题下的最左列
    SpanRows[Right] = new SpanInfo(Text, 3, ColIndex, Right); //添加该标题下的最右列
    for (int i = ColIndex + 1; i < Right; i++) //中间的列
    {
      SpanRows[i] = new SpanInfo(Text, 2, ColIndex, Right);
    }
  }
  /// <summary>
  /// 清除合并的列
  /// </summary>
  public void ClearSpanInfo()
  {
    SpanRows.Clear();
    //ReDrawHead();
  }
  private void DataGridViewEx_Scroll(object sender, ScrollEventArgs e)
  {
    if (e.ScrollOrientation == ScrollOrientation.HorizontalScroll)// && e.Type == ScrollEventType.EndScroll)
    {
      timer1.Enabled = false; timer1.Enabled = true;
    }
  }
  //刷新显示表头
  public void ReDrawHead()
  {
    foreach (int si in SpanRows.Keys)
    {
      this.Invalidate(this.GetCellDisplayRectangle(si, -1, true));
    }
  }
  private void timer1_Tick(object sender, EventArgs e)
  {
    timer1.Enabled = false;
    ReDrawHead();
  }
  /// <summary>
  /// 二维表头的背景颜色
  /// </summary>
  [Description("二维表头的背景颜色"), Browsable(true), Category("二维表头")]
  public Color MergeColumnHeaderBackColor
  {
    get { return this._mergecolumnheaderbackcolor; }
    set { this._mergecolumnheaderbackcolor = value; }
  }
  private Color _mergecolumnheaderbackcolor = System.Drawing.SystemColors.Control;
  #endregion
}

